CVE-2026-103883
8.8, highSixstorage 6Storage Rentals Improper Authentication Vulnerability
- CVSS
- 8.8, high high CVSS v3.1
- EPSS, next 30 days
- n/a
- Exploitation
- No public evidence
- Published
- 11 Nov 2026yesterday
Description
The 6Storage Rentals plugin for WordPress is vulnerable to Authentication Bypass leading to Administrator Account Takeover in all versions up to, and including, 2.31.0. The vulnerability exists because the `six_storage_portal_registration()` AJAX handler (registered on `wp_ajax_six_storage_portal_plugin_registration`) performs no capability check and no nonce verification before writing the caller-supplied `six_storage_online_api_url` POST parameter to the site-wide option of the same name; the unauthenticated `six_storage_create_wp_user()` handler then redeems a transient seeded from that attacker-controlled URL's response and unconditionally calls `wp_set_current_user()` and `wp_set_auth_cookie()` with no ownership or credential verification. This makes it possible for authenticated attackers, with Subscriber-level access and above, to authenticate as any existing WordPress user (including any administrator whose email address is known or guessable) resulting in full site compromise. This issue represents an incomplete fix for a prior vulnerability: the 2.29.0 remediation moved the target email out of POST data into a server-side transient, but because any Subscriber can still overwrite the outbound API URL that populates that transient, the full authentication bypass chain remains exploitable in three AJAX requests.
Details
- Vendor
- Sixstorage
- Product
- 6Storage Rentals
- Weakness
- CWE-287 (opens in a new tab)
- Status
- Deferred
- Updated
- 11 Nov 2026
- Assigner
- security@wordfence.com
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
References 6
Other references 6
- plugins.trac.wordpress.org /browser/6storage-rentals/tags/2.31.0/inc/Base/Six_Storage_DashboardController.php#L14 (opens in a new tab)
- plugins.trac.wordpress.org /browser/6storage-rentals/tags/2.31.0/inc/Base/Six_Storage_DashboardController.php#L4126 (opens in a new tab)
- plugins.trac.wordpress.org /browser/6storage-rentals/tags/2.31.0/inc/Base/Six_Storage_SignInControllerSixStorage.php#L90 (opens in a new tab)
- plugins.trac.wordpress.org /browser/6storage-rentals/tags/2.31.0/inc/Pages/Admin/Six_Storage_WpAdmin.php#L39 (opens in a new tab)
- plugins.trac.wordpress.org /browser/6storage-rentals/tags/2.31.0/inc/Pages/Admin/Six_Storage_WpAdmin.php#L708 (opens in a new tab)
- wordfence.com /threat-intel/vulnerabilities/id/67b82539-8582-4bb4-ad4c-b626233b6075?source=cve (opens in a new tab)
The kind is read from NVD's tags where present and from the shape of the URL otherwise, so treat it as a hint.
Beyond this page
Is CVE-2026-103883 in your network?
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Assembled from the NVD 2.0 API, the CISA Known Exploited Vulnerabilities Catalog and FIRST EPSS. Scores are as of our last collection on 12 Nov 2026, not the live upstream state.